Obituary: Donald Dahlsten

24 September 2003

Donald Dahlsten
Donald Lee Dahlsten, a professor of insect biology, died Sept. 3 at Alta Bates Medical Center after a two-year battle against a rare type of skin cancer. He was 69.

Over the course of his 40-year career, Dahlsten developed a reputation as one of the world’s most respected leaders in biological control, a field that gained momentum in the 1960s as an alternative to the increasingly ineffective use of chemical pesticides. His research focused on the development of ecologically sensitive methods for controlling insects that feed on trees in forests and in urban environments.

Dahlsten may be best known to the general public for his work on psyllid pests, which attack varieties of eucalyptus trees. In addition, he distinguished himself with his research on the population dynamics of tree-killing bark beetles and the factors that attract their natural enemies. His other projects included research on how the methods used to control Pierce’s Disease, which affects grapevines and is spread by the glassy-winged sharpshooter, impacted riparian habitats, and on the ecological impact of the Sudden Oak Death pathogen, a fungus-like algae that has killed tens of thousands of oak trees throughout the state.

He had also maintained one of the largest databases of insectivorous birds in California’s forests and riparian areas, and recently contributed a 20-page chapter on the biology of the chestnut-backed chickadee for Birds of North America. As late as mid-June, Dahlsten was still banding birds for study in southern California with the help of his wife of 38 years, Janet Dahlsten, and his grandson, Joel Smith.

From football to science
Dahlsten was born on Dec. 8, 1933, in Clay Center, Neb., but moved to Los Angeles with his parents when he was 8 years old. He attended UC Santa Barbara on a football scholarship, but had to leave after just one year after contracting polio in 1952. The bout with polio shifted Dahlsten’s career aspirations from football to science. He enrolled at UCLA before transferring to UC Davis, where he received his bachelor’s degree in entomology in 1956. He continued his graduate studies at Berkeley, receiving his M.S. and Ph.D. degrees in entomology in 1960 and 1963, respectively.

After finishing his studies, he taught at the Los Angeles State College for one year before coming back to Berkeley as an assistant entomologist. He worked his way up to a tenured faculty position by 1969, and from 1981 to 1988 he served as chair of the former Division of Biological Control.

A dedicated educator, Dahlsten was appointed associate dean for instruction and student affairs at the College of Natural Resources in 1996. He advised 39 graduate students during his tenure, but he also extended his enthusiasm for insects and education beyond the campus by developing and heading outreach programs through the college and through the campus’s Interactive University Project.

Dahlsten is survived by his parents, Leonard and Shirley Dahlsten of Los Angeles; his wife, Janet, of Berkeley, and her children, Karen Haymaker of Phoenix, Ariz., and Michael Thurston of Auburn, Calif.; Dia Smith of Hollister, Calif., and Andrea Schwipper of Ramona, Calif., his daughters from a previous marriage; his brother, David Dahlsten of Los Angeles; and 10 grandchildren.

A tree-planting ceremony and a memorial service in honor of Dahlsten are scheduled for Sunday, Oct. 12, at noon on the northwest lawn of Giannini Hall. Details will also be available through the College of Natural Resources website at nature.berkeley.edu.

Donations can be made in Dahlsten’s memory to fund outreach programs benefiting K-12 students. Checks can be sent to the Donald Dahlsten Outreach Fund, c/o the College of Natural Resources, University of California, Berkeley, 101 Giannini Hall, #3100, Berkeley, CA 94720-3100.

— Sarah Yang